.flex {
    display: flex;
}

.flex1 {
    flex: 1;
}

.flex2 {
    flex: 2;
}

.flex3 {
    flex: 3;
}

.flex4 {
    flex: 4;
}

.jcenter {
    justify-content: center;
}

.column {
    flex-direction: column;
}

.row {
    flex-direction: row;
}

.aitem {
    align-items: center;
}

.clearbox {
    box-sizing: border-box;
}

.jaround {
    justify-content: space-around;
}

.jbetween {
    justify-content: space-between;
}